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OBD-II trouble code

P0213: Cold Start Injector 1 Malfunction

A fault in the first cold start injector circuit — an extra injector, separate from the main set, that fires only during a cold crank. The signature symptom is unmistakable: the engine is difficult to start when cold and starts perfectly once it is warm.

Medium severityPowertrainFuel InjectorsDrivable short-term

Quick facts

System
Powertrain
Category
Fuel Injectors
Severity
Medium severity
Drivable
Usually safe to drive short-term
Repair cost range
$90$600
DIY difficulty
Intermediate DIY

What does P0213 mean?

A cold start injector is not one of the regular fuel injectors. It is an additional injector, usually mounted in the intake manifold plenum rather than at a cylinder port, whose only job is to spray extra fuel into the intake during a cold crank. Cold fuel does not vaporize well, and cold intake surfaces condense what does vaporize back into liquid, so a cold engine needs a richer mixture than a warm one to catch and run smoothly. The cold start injector supplies that extra fuel for the few seconds it is needed, then plays no part in normal running. P0213 sets when the control module detects a fault in the circuit for cold start injector number 1.

This is a design you will find mostly on older port-injection gasoline engines — a number of Toyota, Nissan, Mercedes-Benz, Volvo, BMW and Porsche engines from the late 1970s through the 1990s used one — and on a range of diesel engines, where a cold start aid is even more important because a cold cylinder may not reach compression-ignition temperature at all. Modern engines have largely done away with the separate injector, because sequential port injection and direct injection can simply extend the pulse width of the regular injectors during a cold start and achieve the same enrichment with no extra hardware. If your vehicle is recent, confirm it actually has a cold start injector before chasing this code.

What makes P0213 unusually easy to recognize is the symptom pattern. On many systems the cold start injector is not controlled the way the main injectors are. Instead it is switched by a thermo-time switch, a temperature-sensitive switch threaded into the coolant passage that closes the injector's ground circuit only when coolant temperature is below a set point, and that also contains a heating element which limits how long the injector can stay energized so the engine does not flood. Other systems hand the control to the ECM using coolant temperature as the trigger. Either way, the injector only ever operates during a cold crank. That means a failure produces prolonged cranking, hard starting, stumbling and stalling in the first seconds after a cold start — and a completely normal start when the engine is already warm. Very few faults are that specific, and the pattern is by itself a strong confirmation you are in the right place.

The opposite failure is worth knowing too. If the injector leaks or is held open by a stuck thermo-time switch or a shorted circuit, extra fuel enters the intake continuously. That produces a rich-running condition, black smoke, fuel smell, fouled plugs, poor economy, and often a hard start when hot because the engine is flooded. A leaking cold start injector is a classic cause of a rich condition that no amount of work on the main fuel system will resolve.

Diagnosis is straightforward and mostly cheap. Inspect the connector and wiring, measure the injector's coil resistance against specification, test the thermo-time switch's behavior cold and warm, and check the injector for leakage. The parts themselves are modest in price on most applications, though availability can be a real constraint on older or lower-volume vehicles.

Common causes

  • Failed cold start injector — clogged, stuck closed, or an open coil winding
  • Faulty thermo-time switch not closing the circuit when the engine is cold
  • Corroded, loose, or damaged connector at the injector or the thermo-time switch
  • Broken, chafed, or shorted wiring in the cold start injector circuit
  • Leaking cold start injector holding fuel into the intake continuously
  • Blown fuse or failed relay in the cold start circuit
  • Low fuel pressure so the injector cannot deliver its intended volume
  • Failed engine coolant temperature sensor on systems where the ECM controls the injector
  • Fault in the ECM's cold start injector driver circuit

Symptoms

  • Hard starting when the engine is cold — long cranking before it catches
  • Normal, immediate starting when the engine is already warm
  • Rough idle, stumbling, or stalling in the first seconds after a cold start
  • Check engine light with P0213 stored
  • Black smoke, fuel smell, and rich running if the injector is leaking instead of failing closed
  • Poor cold-weather fuel economy
  • Increased emissions during the warm-up period

Diagnostic steps

  1. 1.Confirm the engine actually has a cold start injector. Many modern engines do not, and the code then points at a scan tool or lookup error.
  2. 2.Note the symptom pattern. Hard cold start with a normal warm start is the classic signature and confirms you are looking in the right place.
  3. 3.Locate the cold start injector, usually in the intake plenum rather than at a cylinder port, and inspect its connector and wiring for corrosion, chafing, and backed-out pins.
  4. 4.Measure the injector's coil resistance with the key off and compare it against the specification for your engine. An open or badly out-of-spec reading condemns the injector.
  5. 5.Test the thermo-time switch if the system uses one. It should close the circuit below its temperature threshold and open above it, and its internal heater should limit energized time.
  6. 6.With the engine cold, verify the injector is being commanded during cranking using a noid light or by monitoring the circuit.
  7. 7.Check fuel pressure. A cold start injector cannot deliver its intended volume on low system pressure.
  8. 8.Inspect for leakage. A cold start injector that drips continuously causes rich running rather than hard starting, and is diagnosed by pressurizing the system and watching the injector tip.
  9. 9.On systems where the ECM controls the injector, verify the engine coolant temperature sensor is reading accurately, since a falsely warm reading suppresses cold start enrichment entirely.
  10. 10.Replace the injector only after the wiring, thermo-time switch, fuel pressure, and coolant temperature signal have all checked out.

Repair cost

$90$600

A wiring or connector repair is often $90-$200. A thermo-time switch is typically $30-$120 in parts plus about an hour of labor, and because it threads into a coolant passage the job usually involves losing and topping up some coolant. A cold start injector itself commonly runs $60-$250 in parts with 0.5-1.5 hours of labor, since it is generally accessible on the intake plenum. The wide top of the range reflects older and lower-volume applications where the part is scarce and dealer-only, and cases where a leaking injector has fouled plugs or damaged the catalytic converter through prolonged rich running.

Estimate your repair

Run the numbers for your vehicle

Open the Repair Cost Estimator with fuel injector replacement preselected. Adjust labor rate and vehicle category to fit your situation.

DIY vs shop

This is an intermediate DIY job. It usually involves diagnostic steps, specialty parts, and some careful work in tight spaces. If you have the tools and a service manual or trustworthy video for your specific vehicle, it is achievable in a weekend. Otherwise, a competent independent shop will be faster.

Related codes

Frequently asked questions

What is a cold start injector and does my car even have one?

It is an extra fuel injector, separate from the regular set, mounted in the intake plenum and used only during a cold crank to add the additional fuel a cold engine needs to catch and idle. It was common on port-injected gasoline engines from roughly the late 1970s through the 1990s — a number of Toyota, Nissan, Mercedes-Benz, Volvo, BMW and Porsche engines used one — and on many diesels. Most modern engines have dropped it, because sequential port injection and direct injection can simply lengthen the pulse of the regular injectors to achieve the same enrichment. If your vehicle is recent, verify it actually has the component before chasing the code.

Why does my car only start badly when it is cold?

Because the cold start injector only ever operates during a cold crank. Once coolant temperature rises past the threshold, the thermo-time switch or the ECM stops commanding it entirely, and the engine runs purely on the main injectors — which are working fine. So a failed cold start injector produces long cranking and a stumbling first thirty seconds in the morning, then a perfectly normal restart at lunchtime. That very specific pattern is one of the most useful confirmations in fuel system diagnosis, because almost nothing else behaves that way.

Can a cold start injector cause the opposite problem — running too rich?

Yes, and it is a commonly missed cause. If the injector leaks, or a stuck thermo-time switch or a shorted circuit holds it open, extra fuel keeps entering the intake after the engine has warmed up. You get black smoke, a fuel smell, fouled spark plugs, poor economy, and often a hard start when hot because the engine is flooded. People chase this through the main fuel system and fuel pressure regulator without success. Pressurizing the fuel system and watching the cold start injector tip for drips settles it quickly.

Is P0213 safe to drive with?

In the failed-closed case, generally yes for a short period. The engine is hard to start cold but runs normally once warm, so it is not a safety issue — it is an inconvenience and it does put extra wear on the starter and battery from prolonged cranking. The leaking case deserves more urgency, because continuous extra fuel washes oil off the cylinder walls, fouls plugs, and can damage the catalytic converter through sustained rich running. Either way, get it diagnosed rather than living with it, since the repair is usually modest.

AutoLogicTools provides general automotive planning information. Trouble code interpretations, repair cost ranges, and DIY guidance vary by vehicle, model year, location, parts quality, and shop labor rate. Always verify a diagnosis with a scan tool and a qualified automotive professional before approving repairs.